Apparatus, and associated method, for facilitating antenna weight selection utilizing deterministic perturbation gradient approximation

• US 20040198228A1
• Filed: 04/26/2004
• Published: 10/07/2004
• Est. Priority Date: 05/15/2002
• Status: Active Grant

• Current Assignee: HTC Corporation
• Original Assignee: Balaji Raghothaman
• Inventors: Raghothaman, Balaji
• Granted Patent: US 7,212,838 B2
• Time in Patent Office: Days
• US Class Current: 455/63.1
• CPC Class Codes: H04B 7/0636 Feedback format
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/0854 using error minimizing algorithms, e.g. minimum mean squared error [MMSE], "cross-correlation" or matrix inversion

Abstract

Apparatus, and an associated method, for facilitating selection of optimal antenna weightings by which to weight signals sent in a communication system that utilizes closed-loop transmit diversity. A deterministic perturbation gradient approximation technique is utilized in which perturbation vectors are selected by a selector and applied, by an applicator, to antenna weighting elements. A selected set of perturbation vectors are applied to the antenna weighting elements in both a positive direction and a negative direction. A detector at a receiving station measures in disassociated with the signals communicated thereto, once weighted with the perturbation vectors. A single-bit feedback value is returned to the sending station, and the antenna weightings are appropriately adjusted.

Claims

1-20. -20. Canceled.

21. In a radio communication system having a sending station having a plurality of spaced-apart antennas from which data is selectably sent to a receiving station, an improvement of apparatus for facilitating selection of antenna weightings by which the data is to be weighted by antenna weighters prior to application to individual ones of the antennas of the plurality of antennas, said apparatus comprising:

a perturbation selector embodied at the sending station, said perturbation vector selector for selecting vector values that together define a perturbation vector to be applied to separate ones of the antenna weighters to perturb the values of the antenna weightings in amounts responsive to the vector values selected by said perturbation vector value selector, the vector values selected during a first portion of a selected time period of first values for perturbing the antenna weightings in a first direction and the vector values selected during a second portion of the selected time period also of the first values, but for perturbing the antenna weightings in a second direction; and

a feedback detector embodied at the sending station, said feedback detector for detecting feedback values returned to the sending station by the receiving station, the feedback values formed responsive to weighted data, perturbed during both the first and the second portions, respectively, of the selected time period, the feedback utilized to adjust the antenna weightings responsive to the feedback values.

33. The apparatus of claim_wherein the feedback values detected by said feedback detector are of single-bit lengths.

34. In a method of communicating in a radio communication system having a sending station having a plurality of spaced-apart antennas from which send data is selectably sent to a receiving station, an improvement of a method for facilitating selection of antenna weightings by which the send data is to be weighted by antenna weighters prior to application to individual ones of the plurality of antennas, said method comprising the operations of:

selecting vector values that together define a perturbation vector; and

applying the vector values selected during said operation of selecting to separate ones of the antenna weighters to perturb the values of antenna weightings in amounts responsive to the vector values, the vector values applied during a first portion of a selected time period for perturbing the antenna weightings in a first direction and the vector values applied during a second portion of the selected time period for perturbing the antenna weightings in a second direction.